Butterfly valves have been used at the base of tank trailers, or even railroad cars, as a means to prevent the untimely discharge of the conveying cargo, whether it be grains, polymer beads, or other flowable materials, in order to provide the means for preventing the unauthorized and untimely discharge of the conveying load, but at the same time, through their manipulation into an opened position, allows for prompt discharge of such materials. Currently, before this invention, the operator of the vehicle was required to climb under the tank trailer and in the early days, apply a wrench to the butterfly valve shaft, and forcefully turn it at least a quarter turn, in order to provide for an opening, or closing, of the valve, during its manipulation and operation. The problem with such structure was its accessibility, because the operator was required to crawl deeply under the vehicle, to get access to the shaft, and to attain its manipulation, during usage. During inclement weather, obviously, it is a dirty job, but, regardless of the weather, it was still predominantly a difficult task, if not even to so extent potentially hazardous, to be so close to the point of discharge, of the bulk granular material during it's processing.
While substantial design and development of the configuration of the butterfly valve has taken place over the years, as for example, since the conveying material may be a potential food product, the butterfly valve had to work completely effectively to prevent the entrance of any insects, vermin or rodents, into the tank trailer, and thereby obtaining a contaminating access to the conveyed load. Thus, the butterfly valves were designed to prevent that type of access, and to function to completely clean out the conveying tank trailer, since leaving any of the previous load intact, even a singular grain of a polymer bead that may be used in blow molding of vessels, a singular bead could containment and prevent the usage of any vessels or bottles molded from the previous load, if contamination occurred. For example, if white polymer beads, for use for injecting and blow molding, are conveyed in a current load, and the previous load had black polymer beads, with one of the black beads remaining and intermixing with the white beads can completely contaminate and prevent the usage of any bottles molded, as for example, milk jugs, since black streaks may be present in any currently molded bottles due to previous contamination. Thus, substantial investment of time, research, and funds were made to prefect the butterfly valve, but gave little or no thought to the convenience of the vehicle operator, when required to manipulate such valves during their functioning.
As a result, the current invention has been designed to give consideration to the safety and convenience of the vehicle operator, to facilitate his/her manipulation of such valves, when arriving at the site of refilling of a tank trailer, or to attain it's unloading.
Examples of prior art butterfly valves can be seen in the previous patent to Sisk, the inventor herein, as shown in his U.S. Pat. No. 5,360,030, disclosing a butterfly valve incorporating sleeve seals. Other examples of butterfly valves used in pipelines include U.S. Pat. No. 3,100,500, upon a disc valve with removable seat and unitary stem; U.S. Pat. No. 3,334,650, upon a Valve; U.S. Pat. No. 3,778,028, upon a Lined Butterfly Valve; and, the Butterfly Valve Assembly as shown in U.S. Pat. No. 3,904,173.
An example of a swing-away hopper tee, that is integrated with the tank trailer and rendered operative by means of a butterfly valve, can be seen in the U.S. Pat. No. 6,786,362, to David Sisk, the inventor herein. It can be noted, for example, in its FIG. 3, just how the various operating components that connect with the hopper flange and would swing away to provide clearance, may easily get in the way of its associated operating lever, as noted, which the subject matter of this current invention, through the use of its extension, and contoured handle, clears any such obstruction.